This protocol leaves the system in the same state as the one before
the measurement. So the whole process constitutes a cycle whose
outcome is to extract \(\log 2\)  units of work from the system, in
apparentLater Landauer [1]}
showed that, considering the cost of storing the measurement in a
memory, no violation of the second law of thermodynamics occurs.
violation of the second law of thermodynamics. It has recently been
realised [2]}, [3]}
that, measuring a quantity \(M\)  during an isothermal cyclic transformation,
allows an observer to extract, on average, an amount of work
\(\mathbb {E}[W]\;\le \; TI(Y,M)\) 
